1. Field of Invention
The present invention pertains generally to devices for carrying self-supporting sheet-like articles such as printed circuit boards and the like, and pertains more particularly to a printed circuit board carrier that is easy to manufacture and can be easily assembled and later disassembled for compact storage and transporting from point of manufacture to point of use. For purposes of this specification and the concluding claims, it is understood that the term "self-supporting sheet-like article" means a thin article having appreciable width and depth that can be supported generally horizontally at its edges without collapsing under its own weight and the weight of other objects that it is intended to carry.
Printed circuit boards (hereinafter "PCB's") are widely used in the electronics industry to support and interconnect electronic components and often need to be handled in batches of large numbers. It is, therefore, convenient to arrange PCB's in uniform stacks such that they are parallel to and uniformly spaced apart from each other, in order to minimize their stored or processed volume. PCB carriers designed to accommodate a number of boards so arranged can be stored, transported or otherwise handled as necessary, without handling of the individual PCB's in the carrier.
It is desirable for such carriers to be capable of being stacked upon one another vertically. It is also desirable to be able to transport such carriers manually, or to fix them in place simply and quickly in a truck or other vehicle for secure longer distance transport. Such carriers should also be light, durable, and preferably capable of disassembly for storage when not in use. In addition, carriers of this type should be designed to be supported in any of a number of ways, such as by resting on a shelf, or by being suspended.
Since PCB's are not all of the same size, it is also desirable to be able to adjust the size of a carrier to accommodate PCB's of different dimensions.
2. Description of the Prior Art
One carrier of the general type described above has been disclose in U.S. Pat. No. 4,385,781 (Welsch et al.), and assigned in common with the present application. While the carrier disclosed in that patent fulfills most of the above requirements, it has been found in some applications that it is desirable to provide the carrier, shown in the Welsch patent, with additional rigidity and stability. In particular, the carrier disclosed in the Welsch patent is reasonably rigid in the front-to-back direction, but is not as sturdy as desired for some purposes in the side-to-side direction.